Electrostatic chuck base machining sealing tool

Abstract

The utility model discloses an electrostatic chuck base machining sealing tool which comprises a cylindrical base, a bolt hole corresponding to the base is formed in the base, the interior of the base is hollow to form a cavity, a plurality of ejector pins are arranged in the cavity, and the ejector pins correspond to holes penetrating through the base in size and position in a one-to-one mode. The grinding tool has the beneficial effects that during machining, the base is connected to the back face of the base through the bolt, the hole is sealed through the cooperation of the ejector pin, a sealing cavity is formed, grinding fluid is prevented from making contact with the back face of the base, the grinding tool is prevented from being damaged, and the service life of the grinding tool is prolonged. The grinding fluid is effectively prevented from corroding holes and the back surface of the base; double-layer sealing is achieved, compressed air is introduced into the device, on one hand, trace infiltration of grinding fluid is guaranteed, on the other hand, internal dryness is guaranteed, and moisture is prevented from entering.

Description

Technical Field

[0001] The utility model relates to the technical field of electrostatic chucks, in particular to a processing and sealing tooling for an electrostatic chuck base. Background Art

[0002] An electrostatic chuck mainly consists of a dielectric layer, a DC electrode, a RF electrode, etc. Among them, the dielectric layer usually adopts a ceramic material, such as aluminum nitride, which has good heat conduction performance. The DC electrode is embedded in the dielectric layer and used to connect to a high-voltage DC power supply. The RF electrode provides the RF bias power required during the wafer processing, and this series of components are all installed on the base.

[0003] Generally, the base of an electrostatic chuck is made of aluminum-based material. Its internal cooling channels are respectively processed by a machine tool, and then connected to each other through diffusion bonding, vacuum brazing or electron beam welding. Then, connection holes are processed. Finally, the upper surface is ground by a grinding machine to form the base. Generally, through holes for ejector pins are provided on the base. In the later stage, ejector pins are installed inside to jack up the workpiece on the upper surface for convenient blanking. There are also through ventilation holes, as well as non-through DC connection holes and cooling channel connection holes. During the grinding process of the base, the base is fixed on the grinding machine and ground by a grinding wheel. During the process, grinding fluid is continuously sprayed on the base. Due to high precision and small grinding amount, the grinding processing time is long, and the grinding fluid will corrode the base, especially various holes, resulting in large size deviations of the processed holes. At the same time, pins made of metal materials are inserted into the DC holes on the back surface, and the grinding fluid will also corrode the pins. At the same time, if the grinding fluid penetrates into the pins, when the pins are connected to a high-voltage power supply later, it is very easy to cause breakdown, damaging the raw materials and the chuck. Therefore, a transfer tooling is needed to effectively isolate the back holes from the grinding fluid during processing to prevent the grinding fluid from oxidizing the back surface of the chuck. In addition, during processing, various clamping tools will also cause certain damage to the outer surface of the base, affecting the product quality. Summary of the Utility Model

[0004] In order to solve the above technical problems, the utility model provides a processing and sealing tooling for an electrostatic chuck base.

[0005] The specific technical solution is as follows:

[0006] An electrostatic chuck base processing sealing tooling, including a cylindrical base, the base is provided with bolt holes corresponding to the base, the interior of the base is hollow to form a cavity, and a plurality of thimbles are arranged in the cavity. The thimbles correspond to the holes penetrating through the base in terms of size and position one by one. When the base is bolted to the base, the thimbles are inserted into the holes of the base. A waterproof glue is also applied at the connection between the base and the base, and a hard anodized film layer is provided on the outer wall of the base; the thimble specifically includes a thimble sleeve and a movable part. The thimble sleeve is provided with a vertical installation groove and an arc-shaped adjustment groove, the installation groove communicates with the adjustment groove, and a plurality of limiting grooves are provided on the adjustment groove. The upper part of the movable part is the same size as the hole penetrating through the base, and a protrusion is provided on the lower side of the lower part of the movable part. The material used for the movable part is the same as that of the base material, and a spring is also provided at the lower part of the thimble sleeve.

[0007] A ring-shaped groove is provided on the upper surface of the base, and a sealing gasket is arranged in the ring-shaped groove. The height difference between the sealing gasket and the upper surface of the base is 0-2 mm, and at least one of the ring-shaped groove and the sealing gasket is provided.

[0008] A circular ring is arranged in the cavity of the base to divide the cavity of the base into an inner cavity and an outer cavity. The thimbles are arranged in the inner cavity, and the height of the upper surface of the circular ring is the same as the height of the upper part of the base.

[0009] A ring-shaped groove is also provided on the upper part of the circular ring, and the sealing gasket is arranged in the ring-shaped groove, and at least one of the sealing gaskets is provided.

[0010] A first air hole is provided on the side of the base, and an air compressor is connected to the first air hole.

[0011] A second air hole and a third air hole are provided on the side of the base. The second air hole and the third air hole are respectively connected to the inner cavity and the outer cavity. The second air hole and the third air hole are both connected with an air compressor, and the pressure in the inner cavity is greater than or equal to the pressure in the outer cavity.

[0012] Compared with the prior art, the technical solution proposed by the present invention has the following advantages:

[0013] (1) During processing, the base is bolted to the back of the base, and the thimbles are used to close the holes to form a sealed cavity, preventing the grinding fluid from contacting the back of the base, effectively preventing the grinding fluid from corroding the holes and the back of the base;

[0014] (2) Double-layer sealing, and compressed air is introduced into the interior at the same time. On the one hand, it ensures a small amount of infiltration of the grinding fluid, and on the other hand, it ensures the internal dryness and prevents moisture from entering. Description of the Drawings

[0015] To more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0016] Figure 1 It is a distribution diagram of the holes on the back of the electrostatic chuck;

[0017] Figure 2 It is a schematic diagram of the connection between the base and the pedestal;

[0018] Figure 3 It is a cross-sectional view of the pedestal in the embodiment;

[0019] Figure 4 It is a schematic diagram of the thimble structure;

[0020] Figure 5 It is a cross-sectional view of the pedestal in the second embodiment. Specific implementation manners

[0021] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the utility model. The described embodiments are only some embodiments of the utility model, rather than all embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the utility model.

[0022] Please refer to Figure 1 , Figure 1 is a schematic diagram of the back structure of the electrostatic chuck. There are through holes for ejector pins and air holes on both sides of the electrostatic chuck base, as well as cooling channel holes connected to the inside of the base and pin holes connected to the internal electrode layer from the back. These holes need to be processed and formed before the final precision grinding. Finally, the base blank is placed on the grinding machine for precision grinding. During the grinding process of the base, the base is fixed on the grinding machine and ground by the grinding wheel. During the process, grinding fluid is continuously sprayed on the base. Due to the high precision and small grinding amount, the grinding processing time is long, and the grinding fluid will corrode the base, especially various holes, resulting in large size deviations of the processed holes. At the same time, pins made of metal materials are inserted into the DC holes on the back, and the grinding fluid will also corrode the pins. At the same time, if the grinding fluid penetrates into the pins, when the pins are connected to the high-voltage power supply later, it is very easy to cause breakdown, damaging the raw materials and the chuck. Therefore, a transfer tooling is needed to effectively isolate the back holes from the grinding fluid during processing to prevent the grinding fluid from oxidizing the back of the chuck. In addition, during processing, various clamping tools will also cause certain damage to the outer surface of the base, affecting the product quality.

[0023] To solve the problems existing in the related prior art, the present utility model proposes a processing and sealing tooling for an electrostatic chuck base. The principle and structure of the present utility model will be described in detail below with reference to the accompanying drawings and embodiments. Embodiment 1

[0024] Please refer to Figure 2 - Figure 4 , the present utility model proposes a processing and sealing tooling for an electrostatic chuck base, including a cylindrical base 1. The base 1 is provided with bolt holes corresponding to the base. The interior of the base 1 is hollow to form a cavity. A plurality of thimbles 2 are arranged in the cavity. The sizes and positions of the thimbles 2 correspond one by one to the holes penetrating through the base. When the base 1 is bolted to the base, the thimbles 2 are inserted into the holes of the base. A waterproof glue 3 is also provided at the connection between the base and the base. A hard anodized film layer 4 is provided on the outer wall of the base.

[0025] When the thimble 2 is inserted into the hole, in order to prevent the grinding fluid from seeping into the hole, it is necessary to ensure that the upper part of the thimble 2 is equal to or higher than the upper surface height of the chuck base, and then grind together. Therefore, the thimble 2 is a consumable. For the convenience of replacement, the thimble 2 includes a thimble sleeve 2a and a movable part 2b. The thimble sleeve 2a is provided with a vertical installation groove 2c and an arc-shaped adjustment groove 2d. The installation groove 2c communicates with the adjustment groove 2d. A plurality of limit grooves 2e are provided on the adjustment groove 2d. The upper part of the movable part 2b has the same size as the hole penetrating through the base. A protrusion 2f is provided on the lower side of the lower part of the movable part 2b. The material of the movable part 2b is the same as that of the base. A spring 2g is also provided at the lower part of the thimble sleeve 2a. In this way, by inserting the movable part 2b into the adjustment groove 2d through the installation groove 2c, and then adjusting the extending length of the movable part 2b, it is necessary to ensure that the height of the movable part 2b is higher than the height after grinding. In this way, when grinding to the standard thickness, the upper height of the movable part 2b is the same as the upper height of the thimble 2, and the grinding fluid will not enter the hole. When the height of the movable part 2b is not enough to reach the predetermined height, it can be adjusted so that the protrusion 2f slides into a higher limit groove 2e in the adjustment groove 2d. The bottom spring 2g can effectively ensure the lifting effect. When it cannot reach the predetermined height even when adjusted to the highest limit groove 2e, the movable part 2b needs to be replaced in time.

[0026] In use, the electrostatic chuck base is fixed to the base 1 through bolts and tightened. At the same time, the ejector pin 2 is inserted into the through hole on the chuck base, forming a sealed cavity on the back of the base. Then, the whole is placed on a grinding machine for processing. During the processing, the grinding fluid will not contact the holes, ensuring that the holes on the back will not be corroded by the grinding fluid. Meanwhile, the waterproof glue further improves the sealing performance. In addition, the base is anodized to form a hard anodized film layer 4 on the outside, which can increase the hardness of the base 1. When clamping the base 1 with the clamping block, it will not cause damage to the appearance and also improves the corrosion resistance of the base. At this time, the chuck base does not need to be clamped, so it will not cause damage to the surface.

[0027] Please refer to Figure 3 , a ring-shaped groove is provided on the upper surface of the base 1, and a sealing gasket 5 is provided in the ring-shaped groove. The height difference between the sealing gasket 5 and the upper surface of the base 1 is 0 - 2 mm, and there is at least one ring-shaped groove and sealing gasket 5. In this way, when tightened, the sealing gasket can improve the sealing effect and prevent the grinding fluid from seeping into the back of the base from the connection. In addition, a first air hole 7 is provided on the side of the base 1, and an air compressor is connected to the first air hole 7. By introducing compressed air into the cavity, the internal pressure can be ensured to be higher than the external pressure. In this way, even if there are gaps between the movable part 2b and the holes or between the base 1 and the base, the infiltrated water vapor can be blown out through the higher internal pressure, keeping the inside dry and further improving the anti-corrosion effect. Embodiment 2

[0028] Please refer to Figure 5 , a ring 6 is provided in the inner cavity of the base 1, dividing the inner cavity of the base 1 into an inner cavity and an outer cavity. The ejector pin 2 is arranged in the inner cavity. The upper surface height of the ring 6 is the same as the upper height of the base 1. Such a layered double-chamber structure can further improve the sealing effect. In addition, a ring-shaped groove is also provided on the upper part of the ring 6, and a sealing gasket 5 is provided in the ring-shaped groove. There is at least one sealing gasket 5, and the double-layer sealing effectively improves the cleanliness of the inner cavity.

[0029] A second air hole 8 and a third air hole 9 are provided on the side of the base 1. The second air hole 8 and the third air hole 9 are respectively connected to the inner cavity and the outer cavity. The second air hole 8 and the third air hole 9 are both connected to an air compressor. The pressure in the inner cavity is greater than or equal to the pressure in the outer cavity, and the pressure in the inner cavity is relatively large. In this way, even if water vapor enters the outer cavity, it is not easy to enter the inner cavity, improving the cleanliness.

[0030] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An electrostatic chuck base processing sealing tool, characterized in that: The invention comprises a cylindrical base (1), wherein the base (1) is provided with bolt holes corresponding to the base, the base (1) is hollow inside to form a cavity, a plurality of ejector pins (2) are provided in the cavity, the ejector pins (2) correspond in size and position to the holes passing through the base, when the base (1) is bolted to the base, the ejector pins (2) are inserted into the holes of the base, the connection between the base and the base is also provided with a waterproof glue (3), and the outer wall of the base is provided with a hard oxide film layer (4); The ejector pin (2) comprises a needle sleeve (2a) and a movable part (2b); the needle sleeve (2a) is provided with a vertical mounting groove (2c) and an arc-shaped adjustment groove (2d); the mounting groove (2c) is communicated with the adjustment groove (2d); a plurality of limit grooves (2e) are provided on the adjustment groove (2d); the upper part of the movable part (2b) is the same size as the through hole on the base; a protrusion (2f) is provided on the side of the lower part of the movable part (2b); the material used for the movable part (2b) is the same as that of the base; and a spring (2g) is also provided at the lower part of the needle sleeve (2a).

2. The electrostatic chuck base processing sealing tool according to claim 1, characterized in that: The upper surface of the base (1) is provided with an annular groove, and a sealing gasket (5) is provided in the annular groove. The height difference between the sealing gasket (5) and the upper surface of the base (1) is 0-2 mm, and there is at least one annular groove and one sealing gasket (5).

3. The electrostatic chuck base processing sealing tool according to claim 2, characterized in that: A circular ring (6) is provided in the inner cavity of the base (1), dividing the inner cavity of the base (1) into an inner cavity and an outer cavity. The ejector pin (2) is provided in the inner cavity. The upper surface height of the circular ring (6) is the same as the upper portion height of the base (1).

4. The electrostatic chuck base processing sealing tool according to claim 3, characterized in that: The upper part of the circular ring (6) is also provided with an annular groove, and the sealing gasket (5) is arranged in the annular groove, and there is also at least one sealing gasket (5).

5. The electrostatic chuck base processing sealing tool according to claim 1, characterized in that: A first air hole (7) is provided on the side of the base (1), and an air compressor is connected to the first air hole (7).

6. The electrostatic chuck base processing sealing tool according to claim 3, characterized in that: A second air hole (8) and a third air hole (9) are provided on the side of the base (1); the second air hole (8) and the third air hole (9) are connected to the inner cavity and the outer cavity respectively; the second air hole (8) and the third air hole (9) are both connected to an air compressor; and the pressure in the inner cavity is greater than or equal to the pressure in the outer cavity.

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